Currently the key on a keyboard generally comprise a substrate, a keycap and a connecting component movably connected between the substrate and the keycap. The connecting component has a space for an elastic member to go through and move and the elastic member elastically supports between the keycap and the substrate. The substrate is disposed with a circuit layer. The circuit layer is disposed with a switch corresponding to the elastic member. When the keycap is pressed by a finger, the connecting component guides the keycap to move downward and the elastic member is in contact with the trigger switch, thereby reaching the goal of generating a signal by tapping the keys of the keyboard.
As shown in FIG. 15 from a Taiwan patent number TW378767, it discloses an improved structure for the key of the computer. From top to bottom, the key structure comprises a keycap, a connecting component of scissor style, a U-shaped stand, an elastic member, a circuit layer and a substrate. However, it has following drawbacks: (1) Due to the connecting component of scissor style, the U-shaped stand must be in the U shape (the right side of the U-shaped stand forms an opening) and it cannot be designed as a surrounding frame, which results in insufficient structural strength of the U-shaped stand. There is a deformation when being pressed and this affects the action of the connecting component of scissor style. Thereby, the movement of the key being pressed is not smooth and the pressing contact thereof is not reliable; (2) Since the U-shaped stand is utilized, the front and rear sides thereof respectively form two axis holes which are recessed. As a result, only the connecting component of scissor style can be used here and other types of connecting components are not suitable for this design; (3) The lower end foot on the left side of the connecting component of scissor style rubs the substrate. The connecting component is made of plastics while the substrate is made of metal, so that the issue of abrasion of the connecting component of scissor style arises; (4) The connecting component of scissor style must form the opening for accommodating the elastic member, which results in insufficient structural strength of the connecting component of scissor style which tends to slant when being pressed; (5) For fixing the U-shaped stand and positioning the connecting component of scissor style, the circuit layer and the substrate form many holes which are not ideal for waterproof, dust-proof and circuit layout of the circuit layer.
As shown in FIG. 16 from a Taiwan patent publication number TWM482833, it discloses a key structure in which the top side of the metal bending rod pivots on the keycap while the bottom side of the metal bending rod is sildably connected on the sliding groove of the boost plate, thereby forming the connecting component connected between the keycap and the bottom plate. Additionally, the elastic member is disposed between the keycap and the bottom plate to form the key structure. Nonetheless, it has following problems: (1) The metal bending rod is merely a metal wire of which the structural strength is not enough, and it must go through bending molding which is not easy to manufacture and is costly. Also, the precision of manufacturing is hard to control and this therefore affects the yield rate negatively; (2) In the matching between the metal bending rod and the bottom plate, the former is made of metal while the latter is made of plastics so the abrasion of the sliding groove of plastics emerges. In the long run, this abrasion causes the loose connection in terms of the sliding connection. Furthermore, if the bottom plate is made of metal, the metal slides on the metal results in abrasion which affects the durability of the products and harsh noises which bothers the users when operation; (3) For the slim design of the keyboard, the size of the metal bending rod has to be reduced but this makes it even harder to manufacture; (4) Since the metal bending rod serves as the connecting component between the keycap and the bottom plate, it leads to unstable structure, size not easy to control and insufficient precision. Thereby, the movement of the key being pressed is not smooth and the pressing contact thereof is not reliable, and all the actions are done on the bottom plate. Moreover, many unnecessary holes are formed which are not ideal for waterproof, dust-proof and circuit layout of the circuit layer.
Consequently, it is important to provide an improved design for solving the aforementioned problems.